What is the hypotenuse?

The hypotenuse is the longest side of a right triangle, opposite the right angle (90°). It's always longer than either of the other two sides (called legs). In the formula a² + b² = c², c represents the hypotenuse.

How do I know if a triangle is a right triangle?

If the sides satisfy the Pythagorean theorem (a² + b² = c² where c is the longest side), it's a right triangle. You can also check if one angle measures exactly 90°.

Can I use this for any triangle?

No, the Pythagorean theorem only applies to right triangles (triangles with a 90° angle). For other triangles, use the Law of Cosines or other triangle formulas.

What are Pythagorean triples?

Pythagorean triples are sets of three positive integers that satisfy the theorem, like (3,4,5), (5,12,13), and (8,15,17). These are useful for quick calculations and appear frequently in construction and design.

Pythagorean Theorem Calculator – Find Missing Side

Calculate missing sides of right triangles using the Pythagorean theorem. Find hypotenuse or legs with a² + b² = c² formula.

Pythagorean Theorem Calculator – Find Missing Side

Calculate missing sides of right triangles using the Pythagorean theorem. Find hypotenuse or legs with a² + b² = c² formula.

Find*

Which side to calculate

Side a

Length of side a

Side b

Length of side b

Hypotenuse (c)

Length of hypotenuse

📐

Math visualization will appear here

Understanding the Pythagorean Theorem

The Pythagorean theorem states that in a right triangle, the square of the hypotenuse equals the sum of squares of the other two sides: a² + b² = c². This fundamental relationship has countless applications in mathematics, engineering, and everyday problem-solving.

Applications of the Pythagorean Theorem

Common real-world applications:

Construction: Ensuring corners are square and calculating diagonal braces
Navigation: Finding direct distances and shortest paths
Engineering: Structural analysis and force calculations
Computer graphics: Distance calculations and 3D modeling
Physics: Vector analysis and motion problems
Architecture: Roof design and space planning

How to Use This Calculator

Follow these simple steps to get accurate results:

Enter your find
Enter your side a
Enter your side b
Enter your hypotenuse (c)
Click the "Calculate" button to see your results
Review the detailed breakdown and explanation

Why Use Our Pythagorean Theorem Calculator – Find Missing Side?

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Instant, accurate calculations with professional formulas
Mobile-friendly design that works on any device
Privacy-focused - your data never leaves your browser
Educational content to help you understand the results

Frequently Asked Questions

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